1. Field of the Invention
The present invention relates generally to instrument panels and methods of making their covers and, more particularly, to instrument panels having reduced amounts of reflections therefrom and methods of making their covers.
2. Description of the Related Art
Illuminating instrument panels for automobiles, usually placed in the dash of the automobile, show the status of various operations of the automobile. A typical illuminating instrument panel has a front side for positioning toward the viewer, a back side for positioning away from the viewer, a light source at the back side of the panel for illuminating the panel, an overlay in front of the light source which allows some light to pass through and illuminate the panel, and a transparent cover in front of and spaced away from the overlay. Most often an illuminating instrument panel includes a movable dial or indicator in front of the overlay and corresponding graphics printed on the overlay. Such instrument panels include speedometers, gas gauges, engine temperature gauges, and tachometers.
In addition to the above, the typical illuminating instrument panel includes a light-impervious brow extending over the front of the transparent cover for reducing the amount of reflections from the instrument panel directed toward the viewer. For example, ambient light (e.g., from the sun), hits the brow and is absorbed rather than hitting the transparent cover and reflecting back into the viewer's eyes, impairing the viewer's vision.
The light-impervious brow is also present to reduce the amount of reflectance caused by light-colored objects inside the passenger compartment of the automobile. For example, when the viewer wears light-colored clothing, light from the clothing is reflected by the transparent cover. This occurrence is often referred to as the "white shirt syndrome". The cover of the instrument panel is typically designed so that much of the reflection from the clothing is projected toward the brow and not seen by the viewer.
Brows, however, are cumbersome in design, require a substantial amount of material to construct and add weight to the automobile. It would be desirable to control the instrument panel reflections without a brow to provide more automobile design flexibility (both functionally and aesthetically) and to save on material cost and weight of the automobile.
Another problem with current instrument panels is the reduction in clarity of the graphics due to any reflections on the transparent cover's surfaces. When illuminated, the light source in the instrument panel gauge improves the clarity of the graphics, however a loss in graphics clarity is experienced when the panel is not illuminated, which is often the case during the day. For example, when the cover is clear (or 100% transmitting), around 8% of normal daylight reflects back to the viewer (about 4% from the front surface of the instrument panel cover and about 4% from the back surface of the instrument panel cover). This leaves only about 92% of the normal daylight passing through to the overlay.
If the overlay is reflective, then some of the light striking the overlay is reflected back to the viewer with another approximate 8% loss of light through the cover again. In summary, a reduced level of original light finally reaches the viewer to provide an image of the graphics. The loss of light results in diminished clarity of the graphics to the viewer. If the reflections from the transparent cover's surfaces could be reduced, greater clarity of the graphics is achieved.
Another source of reflections is caused by finger prints or other soiling marks on the cover of the instrument panel. It is, therefore, desirable, to have an instrument panel on which soiling marks are easily removed.
It is, therefore, one object of the present invention to provide an illuminating instrument panel which has a reduced level of reflections on the cover and methods for making a cover for such instrument panels.
It is another object of the present invention to provide an illuminating instrument panel which presents more design flexibility than previous illuminating instrument panels.
It is yet another object of the present invention to provide an illuminating instrument panel which does not require a brow.
It is still another object of the present invention to provide an illuminating instrument panel which has improved graphics clarity for the viewer relative to previous illuminating instrument panels and methods for making the covers which have improved graphics clarity.
It is a further object of the present invention to provide an illuminating instrument panel which has a cover on which soiling marks are easily removed and a method for making such a cover.
It is yet a further object of the present invention to provide a fast and cost-effective method for making an instrument panel cover with reflection-reduction properties.